Part Number: MCU-PLUS-SDK-AM243X Tool/software: Hello, so we are currently searching for an option for a ms-exact time-synchronization in our devices. So in general it's about having a suitable 64-bit timestamp to represent the current time (UNIX-time from 1970) in ms. Our current solution is about having a software-timer (from FreeRTOS) which expires every second and we increase a 64-bit variable then. Since our requirements changed and we need ms-resolution we could probably still use this solution, but it would probably be more prone to drift. So we thought about a HWTimer. This is also possible but we will get an interrupt now every ms and we already have some other timers which interrupt every ms. Any other usage as an 64-bit counter is described in the TRM as an cascade which can't be atomic. But it should be atomic and the handling of setting it up with a new timestamp also needs more work. So we want to reduce those interrupts. It's not important to have the timestamp in our application-code but it must be somewhere to be read and incremented. One possibility would be using another core solely for a timer and putting the timestamp into a shared area. But that seems to be a bit of an overkill. But I also noticed some other maybe matching timer-modules from the TRM: GTC and CPTS with the Timer Manager. The GTC is used by us for some startup-time-measurement via all cores since the GTC is the same for all cores. Which also sounds pretty nice regarding a system-wide timestamp. Also it's already a 64-bit-counter. But I am not sure if it's really useable for our ms-resolution, since the clocks which can be configured as sources are not clocking in ms-resolution and it seems I cannot connect a HW-timer as input clock. The CPTS also has 64-counters but seems to be more suited for system-interconnections for low-latency interaction between the Sitara-hw-components. The SDK-documentation also has some additional timer-apis described but there is no deeper explanation for what they can be used. We can just guess that some are reserved for TSN, like the Gptp. So what would be a good possibility to extract some load for an ms-based 64 bit timestamp from the mcu to an external source which can be accessed by the mcu? Would the GTC fullfill all these requirements? Regards, Felix
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